The Emancipation Proclamation, which set our nation on the path to the end of slavery, was signed 150 years ago this month.

This year we should resolve to teach our children the story of our collective history. The past century and a half offers countless tales of bravery and sacrifice to inspire the next generation. Only by sharing our history will we be able to continue our progress over the next 150 years.

President Lincoln’s wartime proclamation in 1863 read that “all persons held as slaves” in rebel states “are, and henceforward shall be free”. This was a noble idea and certainly a brave gesture. But any astute observer at the time would know that it was more aspiration than policy.

The Emancipation Proclamation applied to 3.1 million slaves, but only freed about 70,000 right away. The rest, like my grandmother’s grandparents, would have to wait until the union army advanced south to end the war. It took another seven years for the Fifteenth Amendment to grant African Americans the right to vote. And even then, Jim Crow laws and threats of violence kept many people of color away from the polls.

Before Lincoln signed the Emancipation Proclamation, Frederick Douglass urged patience to his followers. “Lincoln may be slow,” he said, “but he will take no step backward.” Since then, the civil rights movement has seen many slow periods of buildup spiked by sudden crescendos of passion that sparked great change. We have struggled at times to keep this nation moving forward, but we have also committed, like Lincoln, to never move backward.

Fifty years after the Emancipation Proclamation, NAACP founder W.E.B. Du Bois lauded the accomplishments of the burgeoning civil rights movement: “From slavery to freedom, from 4 million to 10 million, from denial of citizenship to enfranchisement, from being owned chattels to ownership of $600 million in property.” Yet Du Bois also warned that achieving justice could take decades – even lifetimes, adding: “The Negro has refused to believe that the present hesitation and hypocrisy of America is final.”

Fifty years after that, civil rights leaders mobilized more than a quarter-million people of all races to fill the capital’s Mall, demanding passage of meaningful civil rights legislation, an immediate end to school segregation, protection of the right to vote and a public works program for all unemployed. The 1963 March on Washington for Jobs and Freedom marked the centennial of the Emancipation Proclamation with a forceful call for social justice.

Another fifty years have passed. We are about to see the first black president begin his second term in office. But in too many ways, our struggles still mirror the struggles of our ancestors. We need to teach our children about the full history of our people. At the dawn of our collective freedom, our ancestors focused on how their children could get the best education; how they could get past persistent discrimination and find jobs; how they could make the justice system work for them rather than against them.

Today, people of color still face major obstacles to education. A black man in America is still six times more likely to be incarcerated than a white man – and three times more likely to be incarcerated than a black man in South Africa at the height of apartheid. We still face rampant discrimination in lending, housing and employment.

And nearly 150 years after the Reconstruction Amendment, some states are imposing new restrictions on voting that target low-income communities and communities of color. Unlike the Jim Crow era, when people broke the law to suppress the vote, politicians are now using the law – photo ID laws, cuts to early voting and registration restrictions – to suppress the vote.

Lincoln’s quiet courage and Douglass’ brash confidence are important sources of inspiration, but the lesson must not end there. We must teach our children about the many heroes who refused to accept the status quo, and who followed Lincoln’s example to never go backward. When our children remember our whole history, they will be more inclined to see themselves as a part of it. And now, more than ever, we need them to see that the story of our movement is not so much the history of the past as it is instruction for the future.